I agree with Alex Lo's points about half the time. And this is one of those:
In short:
Washington is mistaken to assume that Chinese citizens within China are about to rise up against a hated communist party. Not going to happen.
Beijing is mistaken to assume that the Chinese diaspora will automatically support them. Many may (often in the US, Canada, Australia and Britain) and many may not (often in SE Asia).
Wrong assumptions such as these can worsen already frayed relations.
https://www.scmp.com/comment/opinion/article/3095418/mainland-and-overseas-chinese-may-be-worlds-apart-over-china